U.S. patent number 5,027,239 [Application Number 07/456,099] was granted by the patent office on 1991-06-25 for routing a sleeve and conductors in a head-gimbal assembly.
This patent grant is currently assigned to Seagate Technology, Inc.. Invention is credited to Tracy M. Hagen.
United States Patent |
5,027,239 |
Hagen |
June 25, 1991 |
**Please see images for:
( Certificate of Correction ) ** |
Routing a sleeve and conductors in a head-gimbal assembly
Abstract
A sleeve capture apparatus is provided for use with a load beam.
The load beam couples a gimbal to a support arm in a head-gimbal
assembly and the sleeve capture apparatus supports a conductor
sleeve running from the gimbal to the support arm along the load
beam. A first capture member extends from an edge of the load beam
and has a sleeve contact surface for contacting the conductor
sleeve. A second capture member also extends from the edge of the
load beam and has a sleeve contact surface for contacting the
conductor sleeve. A third capture member extends from the edge of
the load beam and has a sleeve contact surface for contacting the
conductor sleeve. The second capture member has its sleeve contact
surface displaced from a line defined generally by the sleeve
contact surfaces of the first and third capture members. It is
displaced by a distance less than the thickness of the conductor
sleeve.
Inventors: |
Hagen; Tracy M. (Minnetonka,
MN) |
Assignee: |
Seagate Technology, Inc.
(Scotts Valley, CA)
|
Family
ID: |
23811421 |
Appl.
No.: |
07/456,099 |
Filed: |
December 22, 1989 |
Current U.S.
Class: |
360/244.2;
360/244.5; 360/245.8; G9B/5.154 |
Current CPC
Class: |
G11B
5/486 (20130101) |
Current International
Class: |
G11B
5/48 (20060101); G11B 005/48 () |
Field of
Search: |
;360/104,106,108 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
2073501 |
|
Oct 1981 |
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GB |
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2123984 |
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Feb 1984 |
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GB |
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0232916 |
|
Aug 1987 |
|
GB |
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Primary Examiner: Heinz; A. J.
Attorney, Agent or Firm: Kinney & Lange
Claims
What is claimed is:
1. A sleeve capture apparatus suitable for use with a load beam,
the load beam used for coupling a gimbal to a support arm in a
head-gimbal assembly and the sleeve capture apparatus for
supporting a conductor sleeve running from the gimbal to the
support arm along the load beam, the sleeve capture apparatus
comprising:
a first capture member extending from an edge of the load beam and
having a sleeve contact surface for contacting the conductor
sleeve;
a second capture member extending from the edge of the load beam
and having a sleeve contact surface for contacting the conductor
sleeve; and
a third capture member extending from the edge of the load beam and
having a sleeve contact surface for contacting the conductor
sleeve, where the second capture member has its sleeve contact
surface displaced from a line defined generally by the sleeve
contact surfaces of the first and third capture members by a
distance less than the thickness of the conductor sleeve.
2. The apparatus of claim 1 wherein the sleeve contact surface of
at least one of the capture members has a contour which is bent to
wrap around at least a portion of the conductor sleeve.
3. The apparatus of claim 2 wherein the second capture member has
the sleeve contact surface which is bent to wrap around at least a
portion of the conductor sleeve.
4. The apparatus of claim 3 wherein the second capture member is
located generally between the first and third capture members along
the edge of the load beam.
5. The apparatus of claim 4 wherein the contour of the bent sleeve
contact surface forms a semi-circle.
6. The apparatus of claim 4 and further comprising:
a fourth capture member extending from the edge of the load beam
and having a sleeve contact surface for contacting the conductor
sleeve.
7. The apparatus of claim 6 wherein the sleeve contact surface of
the fourth capture member has a contour which is bent to wrap
around at least a portion of the conductor sleeve.
8. The apparatus of claim 7 wherein the sleeve contact surface of
the fourth capture member is linearly displaced from the line
defined by the sleeve contact surfaces of the first and third
capture members by a distance less than the thickness of the
conductor sleeve.
9. The apparatus of claim 8 wherein the third capture member is
located generally between the second and fourth capture members
along the edge of the load beam.
10. The apparatus of claim 9 wherein the contour of the bent sleeve
contact surface forms a semi-circle.
11. The apparatus of claim 6 and further comprising:
a plurality of additional capture members extending from the edge
of the load beam, each having a sleeve contact surface for
contacting the conductor sleeve.
12. The apparatus of claim 11 wherein the capture members are
formed integrally with the load beam.
13. An apparatus suitable for coupling a conductor sleeve to a load
beam in a head-gimbal assembly, the apparatus comprising:
a first capture member extending from an edge of the load beam and
having a sleeve contact surface for supporting the conductor sleeve
in a first direction;
a second capture member extending from the edge of the load beam
and having a sleeve contact surface for supporting the conductor
sleeve in a second direction, where the first and second directions
are generally opposite one another;
a third capture member extending from the edge of the load beam and
having a sleeve contact surface for supporting the conductor sleeve
in the first direction, where the conductor sleeve is supported by
the apparatus primarily along a support axis, the support axis
being generally transverse to the first and second directions, and
where the second capture member is located generally between the
first and third capture members.
14. The apparatus of claim 13 wherein the sleeve contact surface of
the second capture member is separated from the sleeve contact
surfaces of the first and third capture members, the sleeve contact
surfaces of the first, second and third capture members being
positioned generally along the support axis by a displacement
distance measured perpendicular to the support axis and being less
than the thickness of the conductor sleeve.
15. The apparatus of claim 14 wherein at least one of the sleeve
contact surfaces has a bent contour for wrapping around a portion
of the conductor sleeve.
16. The apparatus of claim 15 wherein the sleeve contact surface of
the second capture member has the bent contour.
17. The apparatus of claim 15 wherein the sleeve contact surfaces
of the first and second capture members have bent contours.
18. The apparatus of claim 17 wherein the bent contour comprises a
semi-circle.
19. The apparatus of claim 15 and further comprising:
a fourth capture member extending from the edge of the load beam
and having a sleeve contact surface for supporting the conductor
sleeve in the second direction.
20. The apparatus of claim 19 wherein the sleeve contact surface of
the fourth capture member is separated from the sleeve contact
surfaces of the first and third capture members along the support
axis by a displacement distance less than the thickness of the
conductor sleeve.
21. The apparatus of claim 20 wherein the fourth capture member has
the bent contour.
22. The apparatus of claim 21 wherein the third capture member is
located generally between the second and fourth capture members
along the support axis.
23. The apparatus of claim 22 wherein the second capture member has
the bent contour.
24. The apparatus of claim 19 and further comprising:
a plurality of additional capture members extending from the edge
of the load beam, each having a sleeve contact surface for
supporting the conductor sleeve.
25. The apparatus of claim 24 wherein the capture members are
formed integrally with the load beam.
26. A load beam suitable for coupling a gimbal to a support arm and
a head-gimbal assembly and for supporting a conductor sleeve
running from the gimbal to the support arm along the load beam,
comprising:
a resilient section with a first end for attachment to the support
arm and a second end;
a substantially rigid section having a first end coupled to the
second end of the resilient section and a second end for attachment
to the gimbal;
a first capture member extending from an edge of the first end of
the load beam and having a sleeve contact surface for contacting
the conductor sleeve;
a second capture member extending from the edge of the load beam
and having a sleeve contact surface for contacting the conductor
sleeve; and
a third capture member extending from the edge of the load beam and
having a sleeve contact surface for contacting the conductor
sleeve, where the second capture member has its sleeve contact
surface displaced from a line defined generally by the sleeve
contact surfaces of the first and third capture members by a
distance less than the thickness of the conductor sleeve.
27. The apparatus of claim 26 wherein the sleeve contact surface of
at least one of the capture members has a contour which is bent to
wrap around at least a portion of the conductor sleeve.
28. The apparatus of claim 27 wherein the second capture member has
the sleeve contact surface which is bent to wrap around at least a
portion of the conductor sleeve.
29. The apparatus of claim 28 wherein the second capture member is
located generally between the first and third capture members along
the edge of the load beam.
30. The apparatus of claim 29 wherein the contour of the bent
sleeve contact surface forms a semi-circle.
31. The apparatus of claim 29 and further comprising:
a fourth capture member extending from the edge of the load beam
and having a sleeve contact surface for contacting the conductor
sleeve.
32. The apparatus of claim 31 wherein the sleeve contact surface of
the fourth capture member has a contour which is bent to wrap
around at least a portion of the conductor sleeve.
33. The apparatus of claim 32 wherein the sleeve contact surface of
the fourth capture member is linearly displaced from the line
defined by the sleeve contact surfaces of the first and third
capture members by a distance less than the thickness of the
conductor sleeve.
34. The apparatus of claim 33 wherein the third capture member is
located generally between the second and fourth capture members
along the edge of the load beam.
35. The apparatus of claim 34 wherein the contour of the bent
sleeve contact surface forms a semi-circle.
36. The apparatus of claim 31 and further comprising:
a plurality of additional capture members extending from the edge
of the load beam, each having a sleeve contact surface for
contacting the conductor sleeve.
37. The apparatus of claim 36 wherein the capture members are
formed integrally with the load beam.
38. A head-gimbal assemble (HGA) suitable for being connected to a
support arm for moving the HGA about an axis of rotation in a
magnetic recording system where information is recorded on and
retrieved from a magnetic disk, comprising:
a transducer for recording and retrieving the information;
a slider, coupled to the transducer, for providing a lifting force
to allow the transducer to fly over the disk;
a gimbal, coupled to the slider, for providing a resilient
connection to the slider;
a load beam having a first end coupled to the support arm and
having a second end coupled to the gimbal;
conductor means, coupled to the transducer and the load beam, for
carrying electric signals to and from the transducer;
a first capture member extending from an edge of the first end of
the load beam and having a contact surface for supporting the
conductor means;
a second capture member extending from the edge of the load beam
and having a contact surface for supporting the conductor means;
and
a third capture member extending from the edge of the load beam and
having a contact surface for supporting the conductor means, where
the second capture member has its contact surface displaced from a
line defined generally by the contact surfaces of the first and
third capture members by a distance less than the thickness of the
conductor means.
39. The apparatus of claim 38 wherein the contact surface of at
least one of the capture members has a contour which is bent to
wrap around at least a portion of the conductor means.
40. The apparatus of claim 39 wherein the second capture member has
the sleeve contact surface which is bent to wrap around at least a
portion of the conductor means.
41. The apparatus of claim 40 wherein the second capture member is
located generally between the first and third capture members along
the edge of the load beam.
42. The apparatus of claim 41 wherein the contour of the bent
sleeve contact surface forms a semi-circle.
43. The apparatus of claim 41 and further comprising:
a fourth capture member extending from the edge of the load beam
and having a contact surface for contacting the conductor
means.
44. The apparatus of claim 43 wherein the contact surface of the
fourth capture member has a contour which is bent to wrap around at
least a portion of the conductor means.
45. The apparatus of claim 44 wherein the contact surface of the
fourth capture member is linearly displaced from the line defined
by the contact surfaces of the first and third capture members by a
distance less than the thickness of the conductor means.
46. The apparatus of claim 45 wherein the third capture member is
located generally between the second and fourth capture members
along the edge of the load
47. The apparatus of claim 46 wherein the contour of the bent
contact surface forms a semi-circle.
48. The apparatus of claim 43 and further comprising:
a plurality of additional capture members extending from the edge
of the load beam, each having a contact surface for contacting the
conductor means.
49. The apparatus of claim 39 wherein the capture members are
formed integrally with the load beam.
50. The apparatus of claim 38 wherein the conductor means
comprises:
at least one wire; and
a conductor sleeve disposed about the periphery of the wire.
Description
BACKGROUND OF THE INVENTION
This invention relates to a head-gimbal assembly in a hard disk
file. More particularly, the invention relates to routing
conductors and a conductor sleeve running from a gimbal to a
support arm along a load beam in the head-gimbal assembly.
A head-gimbal assembly (HGA) used in a hard disk file consists
essentially of three components. The first component is a slider
which features a self-acting hydrodynamic air bearing and an
electromagnetic transducer used for recording and retrieving
information from a spinning magnetic disk.
The second component is a gimbal which is attached to the slider.
The gimbal is resilient in the slider's pitch and roll directions
to allow the slider to follow the topography of the disk over which
it is flying. Also, the gimbal is rigid in the in-plane directions
for maintaining precise in-plane slider positioning.
The third component is a load beam which is attached to the gimbal
and to a support arm. The load beam is connected to the support arm
by a well known technique referred to as swaging or ball staking.
The load beam is resilient in the vertical direction. This
resiliency allows the slider to follow the topography of the disk.
As with the gimbal, the load beam is rigid in the in-plane
directions. The load beam also acts as a spring supplying a
downward force that counteracts the hydrodynamic lifting force
developed by the air bearing.
Electrical signals are sent to and received from the
electromagnetic transducer via very small conductors. The
conductors are typically twisted copper wires. There are usually
two conductors, but the number of conductors may vary.
The wires are routed generally along a longitudinal axis of the
load beam from the transducer to the support arm. The wires are
placed inside a flexible sleeve or tube to protect them from being
damaged. The conductor sleeve or tube is secured to the load beam
by bendable metal tabs. HGA's typically have one metal tab at the
end of the load beam nearest the slider, another around the
longitudinal mid-point of the load beam and two more at the end of
the load beam nearest the support arm.
The two metal tabs which secure the conductor sleeve to the load
beam at the end nearest the support arm are generally formed
integrally with the load beam and are formed in a U-shape by the
load beam manufacturer. The U-shape of the capture tabs facilitates
placement of the conductor sleeve into the tabs during assembly of
the HGA. As one step in the assembly of the HGA, the U-shape
capture tabs are bent closed around the conductor sleeve to prevent
the conductor sleeve from escaping during subsequent handling of
the HGA.
However, prior to the ball staking operation, a mounting plate is
welded to the load beam. Then, during the ball staking operation,
clamps are applied to certain portions of the load beam and the
mounting plate. To facilitate proper execution of the ball-staking
technique, the capture tabs must maintain certain clearances from
the surfaces of the load beam and the mounting plate. The critical
clearances are related to the thickness and size of the capture
tabs with respect to the load beam and the mounting plate. If these
clearances are not maintained, the capture tabs interfere with the
clamps used in the ball-staking operation causing alignment
errors.
Mere closure of the capture tabs around the conductor sleeve does
not compress the tabs enough to provide the necessary clearances.
Therefore, an additional operation must be performed. After the
capture tabs are closed, they must be compressed until they provide
the necessary clearances.
The compression, however, alters the substantially round
cross-sectional shape of the closed capture tabs into an oblong
shape. This often results in the formation of undesirable metal
burrs on the capture tabs which must be removed by hand. In
addition, the compression operation significantly distorts the
conductor sleeve and frequently damages it. In some cases, the
conductors inside the conductor sleeve are crushed and damaged as
well.
SUMMARY OF THE INVENTION
The present invention provides a sleeve capture apparatus suitable
for use with a load beam in a head-gimbal assembly. The apparatus
is not required to undergo compression to comply with necessary
clearances.
The sleeve capture apparatus supports a conductor sleeve running
from a gimbal to a support arm along the load beam. A first capture
member extends from an edge of the load beam and has a sleeve
contact surface for supporting the conductor sleeve in a first
direction. A second capture member extends from the edge of the
load beam and has a sleeve contact surface for supporting the
conductor sleeve in a second direction. The first and second
directions are generally opposite one another. A third capture
member extends from the edge of the load beam and has a sleeve
contact surface for supporting the conductor sleeve in the first
direction. The conductor sleeve is supported by the sleeve capture
apparatus along a support axis which is generally transverse to the
first and second directions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a magnetic disk in a hard disk file with an
associated support arm and head-gimbal assembly.
FIG. 2A is a bottom view of the head-gimbal assembly shown in FIG.
1.
FIG. 2B is a side view of the head-gimbal assembly shown in FIG.
2A.
FIG. 2C is a top view of the head-gimbal assembly shown in FIG.
2A.
FIG. 2D is a side view showing conductor connections to a slider of
the head-gimbal assembly shown in FIG. 2A.
FIG. 3 is the opposite side view of head-gimbal assembly shown in
FIG. 2B.
FIG. 4A shows a crimped capture tab of the prior art which is
unacceptable.
FIG. 4B shows a crimped capture tab of the prior art which is
unacceptable.
FIG. 4C shows a crimped capture tab of the prior art.
FIG. 4D shows a crimped capture tab of the prior art which is
unacceptable.
FIG. 5A is a bottom view of the load beam of the present
invention.
FIG. 5B is a side view of the load beam shown in FIG. 5A.
FIG. 6 is an enlarged bottom view of the load beam of the present
invention showing a mounted conductor sleeve.
FIG. 7 is an enlarged sectional view taken along section 7--7 in
FIG. 6.
FIG. 8 is a side view of the load beam shown in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows hard disk file rotary positioning system 10 with load
beam 12 of the prior art. Positioning system 10 includes load beam
12, disk 14, rotary actuator 16, support arm 18, slider 20,
conductor sleeve 22 and signal demodulator and controller 24.
Slider 20 carries an electromagnetic transducer 28 (See FIG. 2A)
which flies over the surface of disk 14 as disk 14 rotates. Slider
20 is coupled to end 21 of load beam 12 by a gimbal (discussed in
greater detail later). Load beam 12 is, in turn, coupled at end 23
to support arm 18 by a known technique referred to as swaging or
ball staking. As rotary actuator 16 pivots about axis 17, slider 20
moves over disk 14 along arc 25 to permit reading from or writing
to different tracks on disk 14.
Signals are written on and retrieved from disk 14 using
electromagnetic transducer 28. Electrical signals are provided to
and received from electromagnetic transducer 28 from signal
demodulator and controller 24 via conductors within conductor
sleeve 22.
FIG. 2A is an enlarged, more detailed view of the head-gimbal
assembly shown in FIG. 1. Load beam -2 is coupled, typically laser
welded, to gimbal 26. Gimbal 26, in turn, is coupled, typically
glued, to slider 20. Slider 20 carries electromagnetic transducer
28 for reading from and writing to disk 14. Electric signals are
provided to and received from electromagnetic transducer 28 via
conductors 30 which are typically twisted wires. Conductors 30 are
threaded through conductor sleeve 22, which protects conductors 30
and helps prevent them from being damaged. Conductor sleeve 22 is
generally made from extruded polytetrafluoroethylene, sometimes
referred to as Teflon TFE.
Load beam 12 is typically provided with four capture tabs for
securing conductor sleeve 22 to load beam 12. The four capture tabs
secure conductor sleeve 22 to load beam 12 to support it as it runs
generally along longitudinal axis 32 of load beam 12 between
transducer 28 and support arm 18. The capture tabs include first
metal tab 34 and second metal tab 36. Metal tabs 34 and 36 are
typically thin, bendable metal tabs. During production of the
head-gimbal assembly, a production person (an assembler) places
conductor sleeve 22 adjacent metal tabs 34 and 36 and bends metal
tabs 34 and 36 over conductor sleeve 22 to secure it in place.
The capture tabs also include formed tabs 38 and 40 which are
typically manufactured in a semi-circle shape. The assembler places
conductor sleeve 22 within the semi-circular capture tabs 38 and 40
and bends tabs 38 and 40 closed or nearly closed around conductor
sleeve 22. Capture tabs 38 and 40 must be closed sufficiently to
prevent conductor sleeve 22 from sliding or moving longitudinally
within tabs 38 and 40. Also, capture tabs 38 and 40 must be closed
sufficiently to hold conductor sleeve 22 within the tabs so that
conductor sleeve 22 does not come loose during subsequent assembly
and handling of the HGA.
FIG. 2B is a side view of the head-gimbal assembly shown in FIG.
2A. FIG. 2C is a bottom view of the head-gimbal assembly shown in
FIG. 2A. FIGS. 2B and 2C use the same reference numerals for the
elements described in FIG. 2A.
FIG. 2D shows the connections of conductors 30 to the
electromagnetic transducer 28 of slider 20. Typically, the
conductors 30 are ultrasonically bonded to connector pads on the
electromagnetic transducer 28.
FIG. 3 is a side view of the head-gimbal assembly of FIG. 2A. FIG.
3 shows the opposite side to that shown in FIG. 2B. Since
ball-staking is used to attach load beam 12 to support arm 18
(shown in FIG. 1), a mounting plate 42 is coupled (typically laser
welded) to end 23 of load beam 12 to facilitate the ball-staking
process. During the ball staking process, clamps interface with
surfaces 44 and 46. Therefore, for the ball-staking technique to
work effectively, the plane of surface 44 of mounting plate 42 and
the plane of surface 46 of load beam 12 must be free from
interference by capture tabs 38 and 40. Otherwise, improper and
misaligned connection may result between load beam 12 and support
arm 18.
As FIG. 3 shows, the capture tabs 38 and 40 protrude above the
plane of surface 46 and below the plane of surface 44. Hence, the
capture tabs of the prior art must be compressed to provide proper
clearance between themselves and the planes of surfaces 44 and 46.
Therefore, during assembly, after capture tabs 38 and 40 are closed
around conductor sleeve 22, the assembler compresses capture tabs
38 and 40 to a proper thickness into an oblong cross-sectional
shape.
FIGS. 4A-4D show cross-sectional views of compressed capture tabs
taken along section line 4--4 in FIG. 2A. FIG. 4A shows capture tab
38 which is not acceptably compressed. In order to be properly
compressed, so that it does not interfere with the ball-staking
technique, capture tab 38 must be compressed between the planes of
surfaces 44 and 46 with some additional clearance to accommodate
production tolerances. In FIG. 4A, capture tab 38 has been closed
sufficiently to hold conductors 30 and conductor sleeve 22.
However, capture tab 38 has not been sufficiently compressed. It is
protruding above the plane of surface 46 and will, therefore,
interfere with the ball-staking technique.
FIG. 4B shows a second, unacceptable capture tab. In FIG. 4B,
capture tab 38 has been compressed, but extends below the plane of
surface 44 of mounting plate 42. Therefore, capture tab 38 will
again interfere with the ball-staking technique.
FIG. 4C shows several drawbacks of the prior art capture tabs. FIG.
4C shows capture tab 38 which has been compressed sufficiently to
remain within the planes of surfaces 44 and 46. However, capture
tab 38 has protruded into sleeve 22, and can damage sleeve 22. If
capture tab 38 protrudes far enough into sleeve 22, it can damage
or break conductors 30.
FIG. 4C also shows another problem which occurs as a result of
compression. Upon being compressed, the surface of the bendable
material forming capture tab 38 fractures or deforms under the
pressure of the compression tool. This results in undesirable metal
burrs, such as burr 48, forming on the surface of capture tab 38.
An additional step must be added to the assembly process to remove
burr 48 by hand.
FIG. 4D illustrates another problem resulting from the compression
technique used in the prior art. Capture tab 38, in FIG. 4D, has
been over compressed causing conductor sleeve 22 to bulge out from
within capture tab 38. This not only causes conductor sleeve 22 to
break the plane of surface 46 and interfere with the ball-staking
operation, but it also damages conductor sleeve 22. If compressed
far enough, capture tab 38 would damage or break conductors 30
within conductor sleeve 22.
All of the problems shown in FIGS. 4A-4D result in unacceptable
head-gimbal assemblies. In order to remedy the problems, additional
steps must be taken during assembly to reposition capture tab 38 or
remove metal burr 48 from capture tab 38. Also, if conductor sleeve
22 is crushed too far and conductors 30 are damaged, the head
gimbal assembly must be scrapped.
FIG. 5A shows a bottom view of load beam 60 of the present
invention. Some of the elements of load beam 60 are the same as
those on load beam 12 of the prior art and are given corresponding
reference numerals. Load beam 60 is provided with bendable metal
capture tabs 34 and 36 which function the same as those shown on
load beam 12.
However, instead of capture tabs 38 and 40, load beam 60 is
provided with four capture members 62, 64, 66 and 68 at end 23.
Capture members 62 and 66 are flat tabs which extend from the edge
of load beam 60. Capture members 64 and 68 also extend from the
edge of load beam 60. However, in this preferred embodiment,
capture members 64 and 68 are formed in the shape of hooks for
supporting conductor sleeve 22.
FIG. 5B is a side view of load beam 60. FIG. 5B shows that,
although capture tabs 62 and 66 extend out from the edge of load
beam 60, they remain substantially in the same plane as load beam
60. However, capture members 64 and 68 extend both away from the
edge of load beam 60 and up, out of the plane of load beam 60.
However, members 64 and 68 are manufactured so they do not break
the plane of either surface 44 or surface 46.
FIG. 6 is an enlarged bottom view of end 23 of load beam 60 showing
conductor sleeve 22 secured to load beam 60 by capture members 62,
64, 66 and 68. As with load beam 12, the assembler places conductor
sleeve 22 adjacent metal tabs 34 and 36. Then, the assembler bends
metal tabs 34 and 36 over conductor sleeve 22 to secure conductor
sleeve 22 to load beam 60. However, rather than threading conductor
sleeve 22 through capture tabs 38 and 40, closing those tabs and
compressing them, as in the prior art, the assembler merely threads
conductor sleeve 22 through capture tabs 62, 64, 66 and 68. FIG. 6
shows that conductor sleeve 22 is placed under capture tab 62, then
threaded up through the hook portion of capture tab 64, then under
capture tab 66 and finally, up through the hook portion of capture
tab 68.
FIG. 7 is a greatly enlarged sectional view taken along section
line 7--7 in FIG. 6. In the embodiment shown, capture tab 68 has a
curved or bent contact surface 70 for contacting conductor sleeve
22. Tab 66 has a substantially flat contact surface 72 for
contacting conductor sleeve 22. Contact surface 70 of capture tab
68 is displaced from contact surface 72 of capture tab 66 in the
vertical direction (given the orientation of load beam 60 in FIG.
7), as shown by arrow 74. In this preferred embodiment, the maximum
distance of displacement between contact surfaces 70 and 72 is less
than the total diameter 76 of conductor sleeve 22 and conductors
30. This results in the vertical position of conductor sleeve 22
varying with the longitudinal position of conductor sleeve 22 along
the edge of load beam 60. For example, the vertical position of
conductor sleeve 22, at the point where it contacts surface 72, is
closer to the plane of surface 44 than the vertical position of
sleeve 22 at the point where it contacts surface 70. The vertical
position of sleeve 22 at the point where it contacts surface 70 is
shown in phantom as 22' in FIG. 7.
In other words, the vertical position of sleeve 22 varies as it is
threaded under tab 66, contacting surface 72, and as it is threaded
over tab 68, contacting surface 70.
FIG. 8 is a greatly enlarged side view of capture tabs 62, 64, 66
and 68 with conductor sleeve 22 threaded through them. The hook
portions of tabs 64 and 68 hold conductor sleeve 22 in close
proximity with the edge of load beam 60. As conductor sleeve 22 is
threaded beneath tab 62, over tab 64, beneath tab 66 and over tab
68, it is snake or wave shaped. The wave shape operates as a cleat
to prevent conductor sleeve 22 from sliding, within tabs 62, 64, 66
and 68, longitudinally in either direction along the edge of load
beam 60.
In one preferred embodiment, the material comprising load beam 60
has a thickness of 0.003 inches and mounting plate 42 has a nominal
thickness of 0.02 inches. Conductor sleeve 22 has a nominal outer
diameter of 0.017 inches. Also, tabs 62, 64, 66 and 68 are formed
integrally with load beam 60 and, thus, have a thickness of 0.003
inches. Ideally, a nominal clearance of 0.002 inches, to
accommodate production tolerances, should exist between the top of
conductor sleeve 22 and the plane of surface 46 as well as between
the bottom of conductor sleeve 22 and tabs 64 and 68 and the plane
of surface 44. Thus, tabs 64 and 68 are formed into shapes
approximating semi-circles and extend downwardly to approximately
0.003 inches from the plane of surface 44 of mounting plate 42.
Also, the capture tabs 64 and 68 are manufactured to terminate
approximately 0.004 inches from the plane of surface 46. This
allows sleeve 22 to snake or wave adequately, yet provide adequate
clearance from the planes of surfaces 44 and 46.
In addition, in this preferred embodiment, tabs 62 and 66 are
formed with a substantially identical length to width ratio and a
length approximately twice that of the outer diameter of conductor
sleeve 22. In plan view, capture tabs 64 and 68 have length and
width dimensions substantially the same as tabs 62 and 66. The
spacing between capture tabs 62, 64, 66 and 68 is approximately
11/2 times the outer diameter of sleeve 22. Also, in the preferred
embodiment, capture tab 62, the capture tab closest to the gimbal
end of load beam 60, is an unformed capture tab, as shown in FIG.
8. The formed and unformed capture tabs alternate along the edge of
load beam 60.
Sleeve 22 is formed of a material such as Teflon TFE which is
flexible to facilitate weaving it through capture tab 62, 64, 66
and 68, yet stiff enough to retain its position within the four
capture tabs. Thus, conductor sleeve 22 cannot escape from the
capture tabs unless deliberately removed. The waviness acts to
cleat the sleeve within the capture tabs to prevent the sleeve from
moving longitudinally within the capture tabs.
It should be noted that the inventive capture tab design could be
implemented using other embodiments. For example, three or five
capture tabs could be used instead of the preferred four. Also, the
formed and unformed capture tabs could be interchanged and the
direction of the hook portion of the formed capture tabs could be
reversed.
CONCLUSION
The present invention provides an apparatus for routing conductor
sleeve 22 and conductors 30 along the edge of load beam 60. The
present invention provides formed and unformed capture tabs 62, 64,
66 and 68. An assembler is capable of threading conductor sleeve 22
through the capture tabs without the use of any tooling aids. Also,
conductor sleeve 22 remains in place within the capture tabs
without the assembler performing the additional step of bending the
capture tabs closed. Further, the capture tabs are formed to
provide adequate clearance for the swaging or ball-staking
technique without requiring the assembler to perform the step of
compressing the capture tabs into an oblong shape.
By eliminating the step of compressing the capture tabs, several
advantages are achieved. First, the time required to assemble the
HGA is reduced. Second, incidents of damage to conductor sleeve 22
and conductors 30 are reduced thereby increasing yield. Also, the
additional step of manually removing metal burrs from the capture
tabs (which are created by the compression step) is eliminated.
Eliminating the production steps and reject HGAs associated with
closure and compression of the capture tabs of the prior art
decreases cost and increases yield.
Although the present invention has been described with reference to
preferred embodiments, workers skilled in the art will recognize
that changes may be made in form and detail without departing from
the spirit and scope of the invention.
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